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Expanding the previously known family of onium (ammonium, phosphonium and sulfonium) organic structure-directing agents (OSDAs) for the synthesis of zeolite MFI, a new member, the arsonium cations, is used for the first time. The new group of tetraalkylarsonium cations has allowed synthesizing the zeolite ZSM-5 with several different chemical compositions, opening a route for the synthesis of zeolites with new series of OSDA. Moreover, the use of As replacing N in the OSDA allows introducing probe atoms that facilitate the study of these molecules by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (MAS-NMR) and X-ray absorption spectroscopy (XAS). Finally, the influence of trivalent elements such as B, Al or Ga isomorphically replacing Si atoms in the framework structure and its interaction with the As species has been studied. We have proved the suitability of tetraalkylarsonium cation for carrying out crystallization of zeolites and also, the benefit of the presence of As atoms in the occluded OSDA, which allows its advanced characterization as well as the study of its evolution during OSDA removal by thermal treatments.
This article was published in the following journal.
Name: Chemistry (Weinheim an der Bergstrasse, Germany)
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